1. SLS009 showed a 46% response rate in R/R AML-MR patients. 2. Median overall survival reached 8.9 months vs. 2.5 months benchmark. 3. No dose-limiting toxicities were observed with SLS009 treatment. 4. Study expansion for SLS009 in newly diagnosed AML is planned for Q1 2026. 5. SLS009 exhibits strong potential against resistance in venetoclax-based therapies.
FAQ
Why Bullish?
The strong clinical results and response rates suggest market potential. Historical price increases have been seen in biotech firms with positive clinical trial results.
How important is it?
The clinical success of SLS009 has potential to significantly drive future revenues. Market perception can shift positively with further study results.
Why Long Term?
Expansion into new patient cohorts indicates sustainable growth prospects for SLS. Long-term approval and market adoption timelines are critical.
SELLAS Life Sciences Reports Promising Phase 2 Data for SLS009 in AML Treatment
On December 7, 2025, SELLAS Life Sciences Group, Inc. (NASDAQ: SLS) announced significant findings from its ongoing Phase 2 study of SLS009, a selective CDK9 inhibitor, during the 67th American Society of Hematology (ASH) Annual Meeting held in Orlando, Florida. This study focuses on the combining SLS009 with azacitidine (AZA) and venetoclax (VEN) for treating relapsed or refractory acute myeloid leukemia (AML) with myelodysplastic syndrome-related changes (AML-MR) in patients previously treated with VEN-based therapies.
Key Study Findings
The combination of SLS009, administered at a dose of 30 mg intravenously twice weekly along with AZA/VEN, achieved notable outcomes:
- Overall response rate across all cohorts: 46%
- Response rate in patients with one prior line of therapy: 58%
- Median overall survival (mOS) for the least pretreated cohort: 8.9 months
- Historical benchmark for similar patient population: approximately 2.5 months
These results reflect the promising activity of SLS009 in a heavily pretreated patient population characterized by high-risk features. A safety evaluation revealed no dose-limiting toxicities (DLTs) were observed during the study.
Clinical Implications and Future Directions
These findings underscore the potential of SLS009 to address resistance to venetoclax-based treatments by inhibiting MCL-1, a known contributor to resistance in AML. Dr. Dragan Cicic, Senior Vice President and Chief Development Officer of SELLAS, emphasized the importance of these results, particularly for patients with ASXL1 and TP53 mutations, which typically indicate a poorer prognosis.
The company is planning to expand the study to evaluate the combination of SLS009 with AZA/VEN in newly diagnosed AML patients exhibiting high-risk features in Q1 2026.
Presentation Details
The study was presented under the title:
- Phase 2 Study of SLS009 in Combination with Azacitidine and Venetoclax for Relapsed/Refractory AML with MDS-Related Changes (AML-MR) After Prior Venetoclax Treatment
Details of the presentation are as follows:
- Date and Time: Sunday, December 7, 2025, 6:00 – 8:00 PM EST
- Session Title: Acute Myeloid Leukemias: Investigational Drug and Cellular Therapies: Poster II
- Location: Orange County Convention Center (OCCC) – West Halls B3-B4
- Lead Author: Joshua F. Zeidner, MD, University of North Carolina, Lineberger Comprehensive Cancer Center
- Publication Number: 3423
About SELLAS Life Sciences Group, Inc.
SELLAS Life Sciences Group, Inc. is a late-stage clinical biopharmaceutical company dedicated to developing innovative therapies for various cancer indications. Its leading candidate, GPS, targets the WT1 protein implicated in numerous tumor types. Additionally, the company is advancing SLS009 (tambiciclib), a differentiated small molecule CDK9 inhibitor aimed at improving outcomes for patients with particularly challenging prognostic factors, including ASXL1 mutations.
For more information about SELLAS and its ongoing projects, visit www.sellaslifesciences.com.